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Research shows that biochemical alpha-D-glucose pentaacetate's insulinotropic function works via an alternative physiological pathway to that involving glucose induction. Experiments designed to investigate insulinotropic action of 1.7 millimolar alpha-D-glucose pentaacetate using rat pancreatic islets are described. Secretory responses to hexose esters are reported.

An analysis of the insulinotropic activities of glutamic acid dimethyl ester (GME) shows that GME enhances insulin production and helps overcome the beta-cell abnormalities in metabolism, phosphorylation and D-glucose transport. GME induces changes in 86Rb outflow, improves 45Ca outflow in L-leucine-treated islet cells and reveals that glibenclamide has insulinotropic potential. The overall O2 uptake gain constitutes the equilibrium between GME oxidation and GME effects on endogeneous fatty acid catabolism.

New, powerful insulin secretagogues are seen in the form of the methyl esters of succinic acid. The incubation of rat islets takes place regardless of the occurrence of D-glucose, and reveals the rise in O2 uptake due to the secretagogues. The islets reveal biosynthetic activity induced by the secretagogues, with a favoured influence on the preparation of proinsulin. Extracellular Ca2+ is missing in the prelabeling of perifused islets which yield 45Ca efflux hindered by the secretagogues. The total uptake of 45Ca is increased and the outflow of 45Ca in islets which are incubated or perifused when extracellular Ca2+ occurs is biphasically induced.

Research was conducted to examine the insulinotropic action of beta-L-glucose pentaacetate on several variables of islet metabolism and function. Results indicate that the insulinotropic action of beta-L-glucose pentaacetate is not attributable to any nutritional value of the ester but seems to result from a direct effect of the ester itself on an unidentified receptor system that leads to a decrease in K+ conductance, induction of electrical activity and plasma membrane depolarization.

Presents a study which examined the mode of ...-D-glucose pentaacetate in islet cells, while focusing on its functional aspects. Role of glucose moiety of ...-D-glucose pentaacetate in its insulinotropic action; Materials and methods used to conduct the study; Findings of the study.